On the irrationality (not irrotationality) of some "experts" (Part 1)

📝 The Technical Rationale and the "Dummy" Trap

One of my first blog articles, "Fluid dynamics for dummies, like me: on potential flows" employed a title with a deliberately dual intention. The term "dummy" was used with ironic sincerity to refer to myself, reflecting my awareness that I am only at the initial stage (the incompressible case) of the vast fields of aerodynamics and fluid dynamics. This self-assessment is, for me, a positive catalyst, fueling the curiosity to learn increasingly complex concepts throughout my professional life. More critically, the title was designed to provoke certain computationalists, journal editors and reviewers who often diminish the relevance of Potential Flow Theory (PFT) as fundamental knowledge of fluid mechanics. These critics argue that PFT holds no place in modern Computational Fluid Dynamics (CFD) given the availability of supercomputers and more fancy computational methods. My intention was to highlight PFT's enduring value for quickly and efficiently simulating certain aerodynamic problems.

Fig. 1 Potential flow solution for a parabolic parachute canopy (for added masses calculation; Pimentel, 2016). Note the clown face in the upper figure.

At that time, a known "potentialist" on LinkedIn misinterpreted the post, viewing it as an attack on his work. Despite my intention being to highlight the computational approach used in his solution, he blocked me without allowing a reply, even attacking my writing style. I believe he was swayed more by the controversial title than by the article's technical content. The irony is that this situation unexpectedly generated a record surge in traffic: over 500 views in two days (five times the usual rate), making it the most-read article on my blog for over two years (see Fig. 2). This episode revealed a powerful lesson: utilizing a defiant language might be the key to publicizing my doctoral research within a CFD community that appears highly entrenched, often rejecting alternative methods or software.

Fig. 2 Hystorical views on my personal blog. The first peak includes the more than 500 visualizations mentioned above.

My intent in discussing PFT was to demystify the idea that it inherently models an inviscid flow (with a free-slip boundary condition). Methods derived from PFT have historically demonstrated excellent agreement with experimental tests (which are naturally viscous). Furthermore, PFT is valid only under specific conditions—assuming perfectly attached flow—a condition that does not exist in real, incompressible high-Reynolds number aerodynamics. This makes PFT a crude simplification that cannot be directly applied (without "corrections") to complex cases involving flow separation. This time, I will not delve into technical discussion, as I have done so extensively in other blog articles. Instead, I prefer to expose the inconsistencies and, in some cases, irrationality I have encountered during this time.

🛑 The Academic Conflict and the Institutional Pyramid

The first major obstacle to my research validation was the loss of my original advisors, who ultimately declined to continue directing my research. My doctoral research extends a potential-based method developed in the 1990s by Prof. Don Durston (NASA Ames Research Center), which improved results by modeling additional detached wakes from a thin flat plate. My work involves extending this model to include the full set of possible detached wakes, including the leading edge. To me, this development is completely logical and follows common sense, validating itself through extensive numerical results after four scientific articles and an patent application (see Fig. 3).


Fig. 3 The four research papers and an international patent application (click on each to follow the link). Dedicated to each one of the five-level pyramid.

My former advisors then called my research "illogical, unphysical, and theoretically unjustifiable". This stands in sharp contrast to the assessment of external experts like Prof. Joseph Katz (San Diego State and Johns Hopkins Universities), who considered the approach valid and encouraged me to pursue my doctoral degree. It is difficult to justify how my former advisors possessed greater expertise to judge this doctoral research than renowned aerodynamicists in a leading aerospace country. The true problem was not the science or methodologies followed, but their unwillingness to engage with evidence presented by a "novice" [1].

However, my ex-advisors were only the first of a five-level institutional problem:

  1. Ex-advisors: Declined supervision, citing "unjustifiable" research.
  2. Academic commission: Refused to resolve the issue, washing their hands by escalating the situation to a higher administrative level.
  3. PhD doctoral coordinator: Supposedly sent the case to the Doctoral School for a formal evaluation.
  4. Doctoral school: After almost half a year, the PhD doctoral coordinator but not the Doctoral School issued an apocryphal report (lacking signature, sent as an open Word file) stating I was dropped for not paying tuition fees!!! without the corresponding notification.
  5. University rector (former administration: 2021-2025): Used the invalid report to issue a final administrative decision.

Unable to file an appeal due to my physical absence from the country and the lack of accessible national legal defense, the situation has now escalated from an administrative issue to a criminal one. This is the result of publicly exposing the anomalies in the process, during the university's rector re-election campaign last April-May, highlighting clear violations of institutional legislation, and even, acts constituting crimes by the previous administration.

Do you want to know how this affected the previous administration? And how the current one and the Justice system is addressing this situation? Stay tuned for the second and third parts of this series!


No step back, whatever the consequences.


The style of this text has been improved by IA (Google Gemini Flash).

[1] On innovation and other hoaxes: a true story at university (Part 1)

Second part: On the irrationality (not irrotationality) of some "experts" (Part 2)

 


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